Alert archive / Maryland / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 140, NWS Philadelphia/Mount Holly

July 20, 2008Cecil County, Maryland; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 20, 2008, 10:13 PM EDT for Cecil County, Maryland; New Castle County, Delaware. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 20, 2008, 10:13 PM EDT (02:13 UTC)
Expired
Jul 20, 2008, 11:15 PM EDT
In force
62 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Cecil County, MD

The radar

The Dover AFB radar (KDOX), 95 km from the middle of the area, began a volume at 02:13 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.2 hours before the alert went out and 158 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2008-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 143 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2008-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
143 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
1969 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS51 KPHI 210213
SVRPHI
DEC003-MDC015-210315-
/O.NEW.KPHI.SV.W.0140.080721T0213Z-080721T0315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1013 PM EDT SUN JUL 20 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN CECIL COUNTY IN NORTHEAST MARYLAND...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...

* UNTIL 1115 PM EDT

* AT 1008 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR CHERRY HILL...OR ABOUT NEAR
  ELKTON...AND MOVING EAST AT 33 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  NEWARK AND GLASGOW BY 1020 PM...
  BEAR AND PIKE CREEK BY 1025 PM...
  STANTON AND 7 MILES NORTH OF SAINT GEORGES BY 1030 PM...
  WILMINGTON MANOR...NEWPORT AND ELSMERE BY 1035 PM...

LAT...LON 3974 7572 3981 7550 3954 7565 3954 7586
      3955 7587 3954 7588 3955 7594 3970 7594
TIME...MOT...LOC 0213Z 264DEG 28KT 3964 7582

$$

EBERWINE
1 follow-up statement
000 
WWUS51 KPHI 210239
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1036 PM EDT SUN JUL 20 2008

MDC015-210246-
/O.CAN.KPHI.SV.W.0140.000000T0000Z-080721T0315Z/
CECIL MD-
1036 PM EDT SUN JUL 20 2008

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CECIL COUNTY IS
CANCELLED...

LAT...LON 3972 7578 3976 7565 3977 7564 3976 7563
      3979 7551 3974 7553 3954 7565 3954 7577
      3955 7577 3954 7578
TIME...MOT...LOC 0236Z 264DEG 28KT 3966 7559

$$

DEC003-210315-
/O.CON.KPHI.SV.W.0140.000000T0000Z-080721T0315Z/
NEW CASTLE DE-
1036 PM EDT SUN JUL 20 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR NORTHERN NEW CASTLE COUNTY...

AT 1034 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR WILMINGTON MANOR...OR
7 MILES SOUTHWEST OF WILMINGTON...MOVING EAST AT 32 MPH.

LAT...LON 3972 7578 3976 7565 3977 7564 3976 7563
      3979 7551 3974 7553 3954 7565 3954 7577
      3955 7577 3954 7578
TIME...MOT...LOC 0236Z 264DEG 28KT 3966 7559

$$

EBERWINE

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 5:20 AM EDTCoastal Flood StatementPHISussex24 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2008Severe Thunderstorm Warnings in Delaware, 2008Every severe thunderstorm warning in 2008

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.